3/28/2006
By: Emily E. Sickbert-Bennett, UNC Health Care
Long before your mother taught you the importance of washing your hands as she lifted you up to reach the sink so you could wash before dinner, the effectiveness of hand washing was first recognized and described by a Hungarian physician, Ignaz Semmelweis, in 1846. Hand washing remains a timeless and effective intervention for preventing the spread of infections.
Hands can pick up disease-causing bacteria and viruses from contaminated environments or from an ill person or animal. Most microorganisms (e.g., bacteria and viruses) can survive on the hands for several minutes to hours. If you touch your mouth, nose or eyes with contaminated hands, these organisms can enter your body and cause infections. In addition, when you touch objects with your contaminated hands, you can spread the microorganisms to other objects that you touch.

Microorganisms that are transferred by hands can cause diseases such as hepatitis A, infectious diarrhea, colds and the flu. Contaminated hands have been linked to outbreaks of disease in the community. For example, a food handler with a hand infection was associated with an outbreak of food poisoning among high school students attending a breakfast. The effectiveness of handwashing in interrupting disease transmission has been demonstrated in several studies conducted in daycare centers where after the introduction of handwashing training or with higher compliance with handwashing, fewer cases of respiratory and diarrheal infections occurred.
By cleaning your hands at key times throughout the day, you can interrupt the transmission of disease-causing microorganisms. You should wash your hands before, during and after preparing food, after using the bathroom, before eating, after touching animals or animal waste, after blowing your nose, after covering your mouth or nose following a cough or sneeze, when your hands are visibly dirty, and you should always clean your hands more frequently when someone in your home is sick. Small children may need assistance with washing their hands and reminders about these important times to wash.
There are many hand-washing products available now — hand washes, hand rubs (generally alcohol-based), hand rinses and hand wipes.
Hand-wash products are the traditional soaps, either liquid or bar, that are used at a sink with water. Some hand wash products contain additional chemicals that assist in killing the bacteria and viruses on the hands in addition to physically removing the organisms. These products are called antibacterial or antimicrobial. Hand-wash products without these chemicals, called non-antimicrobial products, work solely by physically removing the bacteria and viruses from the hands with the action of washing and rinsing at the sink.
When washing your hands with soap, first wet your hands and then apply the soap. Rub your hands vigorously together and scrub all surfaces continuing for 10-15 seconds. Finally rinse your hands well and dry them with a clean paper towel.
For use in your home, antibacterial soaps have not been shown to have a great benefit over non-antibacterial soaps in terms of infection prevention. However, in settings where there are higher levels of contamination (e.g., daycare centers, hospitals), the use of antimicrobial products may be advantageous over non-antibacterial soaps. There has also been some controversy over whether the use of these antimicrobial products results in microorganisms that are more resistant to antibiotics. Currently, there are no data to support that this mechanism occurs naturally in the environment.
Hand rubs, hand rinses, and hand wipes all can be used when sinks are not available and they contain the antibacterial or antimicrobial chemicals that work to kill the bacteria and viruses on your hands. When using a waterless hand hygiene product, apply the product to your hands and rub your hands vigorously together covering all surfaces of your hands until they are dry.
These waterless hand-wash products are convenient to use anywhere because they do not require a sink. However, hand-washing research studies conducted at the University of North Carolina Hospitals found that these products are not as effective as washing your hands at a sink with soap and water in removing or killing some especially hardy types of bacteria or viruses (such as Bacillus anthracis, the bacteria that causes anthrax infections, or norovirus, a virus that is known to cause the “24-hour stomach bug” during winter months).
Hand washing is a simple action that can help protect you from disease when done regularly and thoroughly.
Emily E. Sickbert-Bennett, MS, is a public health epidemiologist for the University of North Carolina Health Care System.